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ORCNext – WP4Development of supercritical technologies

Huisseune Henk

1

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Test facility

Experimental setup• Feeding pump• Pre-heater• Test-section• Cooler• Pressure gauges• Flow meter• Temperature sensors

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Test facility

Test section• Working fluid: R125 or R134a• Uniform cross section: circular

tube• Electrical uniform heat flux (DC

or AC power supply)• Thermocouples

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Measurements

Heat transfer enhancement

• ↓• ↑

(1) Theory (∆) Experimental: = 140±4.4 kg/h; q = 1.44 W/cm²

(2) Theory(x) Experimental: = 140±3.1 kg/h; q = 2.73 W/cm²

(3) Theory (○) Experimental: = 280±5.6 kg/h; q = 3.32 W/cm²

(4 Theory (●) Experimental: = 280±7.8 kg/h; q = 5.20 W/cm²

Variation of the heat transfer coefficient with bulk temperature for forced convection in a heated pipe for carbon dioxide of 78.5bar flowing upwards in a 1.0 diameter vertical pipe.

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Measurements

Wall and bulk temperature as a function of the distance along a vertical heated 1.6 cm diameter pipe for water at 245 bar (1.11 pcrit).

Heat transfer deterioration– Downward flow no unusual behaviour– Upward flow Deterioration

Flow direction1 382 27 Vertical upward2 382 37 Vertical upward3 400 45 Vertical upward4 375 52 Vertical upward5 400 27 Vertical downward6 400 36 Vertical downward7 393 43 Vertical downward8 381 50 Vertical downward

Upward flow Downward flow

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General characteristicsHeat transfer deterioration

Temperature distribution as a function of local bulk enthalpy along heated vertical and horizontal pipes (1.6 cm diameter) for water at 245 bar (= 1.11 pcrit): and

• Comparison upward, downward and horizontal flow

(1) Horizontal pipe – upper surface

(2) Horizontal pipe – lower surface

(3) Vertical pipe – upward flow

(4) Bulk fluid temperature

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Determine influence of parameters

• Heat flux • Mass flow • Flow direction• Pipe diameter

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Poc supercritical HX

• Using the insights obtained from the experiments, a Poc HX wil be designed and tested.

• Results will be used as model vallidation.

• Type: Shell and tube or (spiral) tube-in-tube heat exchanger.

• Built in test setup at Kortrijk.

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Goals and planning

• 01/01/2013 – 31/06/2013: Design test setup with EES• 01/07/2013 – 31/12/2013: Building test setup• From 01/01/2014: Perform measurements on test loop• 31/06/2014 – 31/12/2014: Design a Poc supercritical HX for

model validation

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ORCNext – WP4Development of supercritical technologies

Huisseune Henk

10